be moved, slipping is still further guarded against, by turning in the nails so that their points touch the perch. If the perch be violently swung, the bird bends his legs, and rests with his breast on the perch, thereby lowering his centre of gravity. If a live bird be perched on the finger, it will be felt that it balances itself and does not grip, but it frequently uses the points of its claws, particularly of the hind ones. It the hand be moved forwards, the bird having a tendency to fall backward, it will be found to actually raise its front toes, and stick in the points of the hind claws; far from gripping tighter, it actually grips less tightly. If a sleeping bird be shaken, it awakes and puts down its second foot. If the perch be swung while the bird is asleep, the bird will be observed to move its body in advance of the movements of the perch. Although the sleeping bird usually uses the point of his hind nail, he does not always do so, and sometimes sleeps, obviously not holding the perch, but evidently balancing, the perch being stationary, but if the perch be moved slightly, the hind nail is used immediately. I cannot detect any bending of the leg, when the bird goes to sleep, beyond that which exists when it is awake, nor is the flexure of the last joint of the toes accompanied by a bending of the leg under ordinary circumstances. On the other hand there can be no doubt, that, in the live bird, flexure of the toes is independent of bending of the leg; a live bird can open or close its claws, with the leg straightened, or bent close to the body, and if a bird be under the influence of either, the flexure of leg and foot, simultaneously observed in the dead bird, is not observed. Birds commonly rest with the breast on the perch, in these cases, the claws will be found quite open; it is obvious in this case, that flexure of knee and heel does not cause flexure of the toes. If bending of the leg necessarily caused flexure of the toes, the bird would in some cases evidently be inconvenienced, during incubation for instance. The idea, that the weight of the body tending to bend the leg might so flex the toes as to diminish the fatigue of perching, is obviously erroneous mechanically; for, if the grip of the perch were produced by the contraction of particular muscles, and if the same muscles were employed on the additional labour of preventing flexure of the leg, the two duties would not be so opposed as to make the strain on the muscles less than it would be if they performed but one duty, and the additional duty would increase the load not decrease it. It appears to me, that perching birds really balance themselves, just as mammals and birds on plane surfaces do; that they are enabled to do this just as man is, by means of opposing muscles; that flexure of leg and toes are independently under control of the bird's will as in man; and that the movements found dependent on each other in the dead bird after alteration of the muscles, are independent in the live bird; and that the large surface covered by the toes, the relative lightness of the body, and the soft under-surface and sharp nails of the toes preventing slipping are sufficient to explain how a bird is enabled to sleep perched, just as a horse or a bird sleeps standing on a plane. III.-The Walking Pace in Man. Previous observers have assumed that the path traversed by man in walking is a straight one, that each step is alike, and that in natural walking, the complementary motions are evoked regularly and symmetrically. I have made a great number of observations, and have surveyed and plotted out natural paths across an extended plain, and I find the natural path is a wavy line. If the pace be slow, the deviation from the straight line is greater than if the pace be quick, and this deviation is greatest when the walk is very slow. The sinuous walk of a man slightly intoxicated, is an exaggeration of the normal walk; the difficulty of walking slowly beside a second person without occasionally coming against him, unless touch be kept in some way, is a matter of common observation. It appears that the adoption of sinuous paths in laying out gardens, with a view to imitate nature, is an unconscious imitation (often exaggerated) of the foot paths formed naturally, whenever an extended plain has to be crossed by persons on foot, and this sinuosity is a consequence of the natural walk of man being in a sinuous path, probably by reason of the equilibrium being imper fect, and the movements not strictly symmetrical. 7. List of Diurnal Lepidoptera inhabiting the Nicobar Islands.-By J. WOOD-MASON, Deputy Superintendent, Indian Museum, and L. DE NICE VILLE. (Abstract.) In this paper which will appear in the Journal, Part II, the authors state, that in Mr. F. Moore's paper on the Lepidopterous Fauna of the Andaman and Nicobar Islands, only 23 species of rhopalocerous Lepidoptera are recorded from the Nicobar group. The Museum has recently received from Mr. F. A. De Roepstorff a collection of Nicobar butterflies consisting of thirty-four species, twenty-five of which are recorded, in the present paper, for the first time, and two are described as varieties of known forms. This paper will appear in the Journal, Part II. LIBRARY. The following additions have been made to the Library since the meeting held in February last. TRANSACTIONS, PROCEEDINGS AND JOURNALS, Berlin. K. preussische Akademie der Wissenschaften,-Monatsbericht, Bordeaux. Société de Géographie Commerciale,-Bulletin, No. 2. Feistmantel, Dr. 0.-The Flora of the Talchir Karharbari Beds. Lisbon. Sociedad de Geographia,-Boletin, Second Series, No. 2. London. Royal Microscopical Society,-Journal, Vol. III, Nos. 6 and 6a, Royal Astronomical Society, Monthly Notices, Vol. XLI, No. 1. The Athenæum,-Nos. 2777 to 2780. Nature, Vol. XXII, No. 574, and Vol. XXIII, Nos. 585-588. München. K. b. Akademie der Wissenschaften,-Sitzungsberichte der mathematisch-physikalischen Classe, Parts 2-4, 1880. philosophisch-philologischen und historischen Classe, Vol. II, Part 3, 1879; and Parts 1-3, 1880. Abhandlungen,-historische Classe, Vol. XV, Part 2. philosophisch-philologischen Classe, Vol. New York. American Oriental Society,-Proceedings, October 1880. La Société de Géographie,-Bulletin, Vol. XX, November 1880. Pisa. Società Toscana di Scienze Naturali,-Atti, Processi Verbali, 14th November 1880. Rome. Società degli Spettroscopisti Italiani,-Memorie, Dispensa 9, September 1880. Roorkee. Professional Papers on Indian Engineering, Vol. X, No. 39, February 1881. Vienna. Kaiserliche Akademie der Wissenschaften,-Fontes Rerum Austriacarum, Vol. XLII, Part 2. Archiv für Osterreichische Geschichte,-Vol. LIX, Parts 1-2, and Vol. LX, Part 1. Sitzungsberichte,-mathematisch-naturwissenchaftliche Classe, Part I, Vol. LXXIX, Nos. 1-5; Vol. LXXX, Nos. 1-5: Part II, Vol. LXXIX, Nos. 4-5; Vol. LXXX, Nos. 1-5; Vol. LXXXI, Nos. 1-3: Part III, Vol. LXXX, Nos. 1-5; Vol. LXXXI, Nos. 1—3. philosophisch-historische Classe, Vol. XCIV, Nos. 1-2; Vol. XCV, Nos. 1-4, and Vol. XCVI, No. 1. Yokohama. Deutsche Gesellschaft für Natur-und Völkerkunde Ostasiens, Mittheilungen, December 1880. Asiatic Society of Japan,-Transactions, Vol. VIII, Part 4. Zagreb. Arkeologickoga Druztva,-Viestnik, Vol. III, No. 1. PAMPHLETS, presented by the Authors. LYALL, C. J. Sketch of the Hindustani Language. Sm. 8vo., Edinburgh, 1880. SCHWENDLER, L. Report on the Electric Light at the East Indian Railway Company's Station, Howrah (Calcutta). Fep., Calcutta, 1881. MISCELLANEOUS PRESENTATIONS. CARRINGTON, R. C. List of Light-Houses and Light-Vessels in British India, including the Red Sea and Coast of Arabia (Suez to Singapore). Obl. 4to., Calcutta, 1881. MARINE SURVEY DEPARTMENT. DÖLLINGER, J. v. Das Haus Wittelsbach und seine Bedeutung in der deutschen Geschichte. 4to., Munich, 1880. ROCKINGER, DR. L. Die Pflege der Geschichte durch die Wittelsbacher. 4to., Munich. Zittel, Dr. K. A. Ueber den geologischen Bau der libyschen Wüste. 4to., Munich. K. b. AKAD. DER WISSENS., MÜNCHEN. WRIGHT, W. The Palæographical Society. Fascimiles of Ancient MSS. Oriental Series. Part V. Fol., London, 1880. PALEOGRAPHICAL SOCIETY. Beport on the Administration of the Land Renense Department of the Centri Provinces for the Rerenne year 1979-80 Frp Nagar, 1881. CH. COM CENTRAL PROVINCES. Amount of the Chemtions of the Great Inginimetrical Survey of India, Vol VI. 400. Debra Iran. 1580. Synopsis of the Belts of the Operations of the Great Trigonometrical Survey of Iolia VI VIL 4, Delira Dun, 1579. SURVEYOR GENERAL OF INDIA. Sirteenth Annual Report of the Sanitary Commissioner with the Government of India, 15T9. Fir, Calamina, 18SL SANITARY COMMISSIONER WITH THE GOVERNMENT OF INDIA. Indian Forester, Vol. VI, No. 3. January 1881. PALMER, E. H BENGAL GOVERNMENT. (Sarel Bocks of the East, Vols. VI and IX). The Sto., Oxford, 1880. FALLON, DR. S. W. New English-Hindustani Dictionary, Part I. HOME, REVENCE AND AGRICULTURAL DEPARTMENT. PERIODICALS PURCHASED. Göttingen. Gelehrte Anzeigen,-Nos. 3-4. and Index for 1880. London. Society of Arts,-Journal, Vol. XXIX, Nos. 1469-1471. Vol. XLII. Publishers' Circular,-Vol. XLIV, Nos. 1010-1. Paris. Comptes Rendus,-Vol. XCII, Nos. 1—4. Revue Scientifique, Vol. XXVII, Nos. 2—5. Revue Critique,-Vol. XI, Nos. 2, 4-5. Revue des deux Mondes,-Vol. XLIII, Nos, 2 and 3. Journal des Savants,-January 1881. Annales de Chimie et de Physique,-Vol. XXI, December 1880. Philadelphia. Manual of Conchology, Part 8. BOOKS PURCHASED. GOULD, J. The Birds of Asia. Part XXXII. Fol., London, 1880. GOULD, J. The Birds of New Guinea and the Adjacent Papuan Islands. SALLET, A. VON Die Nachfolger Alexanders des Grossen in Baktrien und Indien. 8vo., Berlin, 1879. |